Method of retrofitting a probe station

ABSTRACT

A method of retrofitting a probe station having a head plate ( 12 ), so that the probe station ( 10 ) is adapted to mate with a predetermined probe card dish ( 16 ) and any tester ( 18 ) out of a set of testers. A depression is then machined into the head plate to create a head plate-tooling plate attachment region. Next, fastening and alignment items are provided and installed in this region. Further, a set of tooling plates ( 110 ) are provided, each having fastening and alignment items adapted to mate to the fastening and alignment items on the attachment regions and defining an aperture designed to engage the predetermined probe card dish. The user may then select a desired one of the tooling plates and mate and fasten the selected tooling plate to the head plate-tooling plate attachment region using the alignment and fastening items.

TECHNICAL FIELD

In the semiconductor field, each set of wafers fabricated is typicallyperformance tested, before they are diced into individual integratedcircuits. FIGS. 1-4 show equipment that is used in this testing.Although these figures show an embodiment of the invention they alsoshow some features that are shared with prior art systems. Thesefeatures are referenced in this section to help explain the context ofthe invention.

To perform wafer testing a piece of equipment known as a probe station10 has a head plate 12 (FIG. 3) that defines an original head plateaperture 14. The aperture supports a circular device known as a probecard dish 16, which in turn supports the probe card 17. A separate pieceof equipment, known as a tester 18 having docking units 20, is loweredinto mating position with respect to the probe station, the probe carddish and the probe card. Sometimes probe station 10 includes anobstacle, such as a wafer loader cover 19, that is too close to theoriginal head plate aperture 14 to permit the docking of a particulartester 18.

INDUSTRIAL APPLICABILITY

The invention applies to the industry of etched semiconductor wafers,which are ultimately diced to produce individual integrated circuits.

BACKGROUND ART

Generally, a number of guides and associated docking equipment piecesare needed to successfully dock a tester to a probe station, a probecard dish and the wafer that the probe card dish supports. Probestations are generally sold to semiconductor manufacturing facilitieswith this docking equipment already installed. Accordingly, when a newtester is purchased it is typically necessary to purchase a new probestation fitted with docking equipment to facilitate docking with the newtester. Unfortunately, the docking equipment, which is typicallyinstalled by the probe station vendor or a secondary source, generallypermits docking to a single make of tester. The installation of dockingequipment to permit the use of a different tester with the probe stationis referred to in the industry as “hardware swap-out” and results inextensive use of technician time and equipment down time.

It is known to machine a single prober to accept a single tooling platethat permits docking to a desired tester. There appears, however, not tohave been an effort in the prior art to produce a set of standardizedtooling plates that could each be used on any one of a set of differingprobe stations. As a result, only very limited flexibility was gained bythis method.

Another issue facing semiconductor manufacturers is the lack ofuniformity of head plate apertures, between the various commercial linesof probe stations. The unfortunate result is that there is currently noknown technique for mating a probe station having a first head plateaperture size with a tester designed to mate with a prober having asecond head plate aperture size.

DISCLOSURE OF THE INVENTION

In a first aspect, the present invention is a method of retrofitting aprobe station having a head plate, so that the probe station is adaptedto mate with a predetermined probe card dish and any tester out of a setof testers. A depression is machined into the head plate to create ahead plate-tooling plate attachment region. Next, fastening andalignment items are provided and installed in this region. Further, aset of tooling plates is provided, each having fastening and alignmentitems adapted to mate to the fastening and alignment items on theattachment regions and defining an aperture designed to engage thepredetermined probe card dish. The user may then select a desired one ofthe tooling plates and mate and fasten the selected tooling plate to thehead plate-tooling plate attachment region using the alignment andfastening items.

In a second separate aspect, the present invention is a tooling platefor installation into a probe station. The plate comprises a rigid platedefining a major aperture and a set of peripheral apertures fitted withspring loaded, retained screws adapted to facilitate fastening to matingthreaded holes.

In a third separate aspect, the present invention is a tooling plate forinstallation into a probe station, the plate comprising a rigid platedefining a major aperture and a set of dowel locator holes precisely setwith respect to the location of the major aperture.

In a fourth separate aspect, the present invention is a method ofretrofitting a probe station having a head plate that defines anoriginal head plate major aperture, so that the probe station is adaptedto mate with a predetermined probe card dish and a predetermined testerthat the probe station could not mate with prior to being retrofitted.The method comprises the steps of machining a depression into the headplate to create a head plate-tooling plate attachment region. Inaddition, the head plate major aperture is enlarged and headplate-tooling plate attachment region fastening and alignment items areprovided. Also provided is a tooling plate having tooling platefastening and alignment items adapted to mate to the head plate-toolingplate attachment region fastening and alignment items and defining atooling plate major aperture designed to engage the predetermined probecard dish and wherein the tooling plate major aperture is positionedrelative to the tooling plate fastening and alignment items such thatonce the tooling plate is installed the tooling plate major aperturewill not be coincident to the original head plate major aperture.Finally, the tooling plate is mated and fastened to the headplate-tooling plate attachment region, using the alignment and fasteningitems.

In a fifth separate aspect, a method of retrofitting a probe stationhaving a head plate, so that it can mate with a tester that includesdocking equipment that extends horizontally beyond the horizontal extentof the probe station. The method comprises machining at least oneattachment region into the head plate and fitting the attachment regionwith alignment and fastening items and providing at least one dockingequipment attachment plate, including a piece docking equipment, to mateto the attachment region. Then the docking equipment attachment plate ismated to the corresponding attachment region so that the dockingequipment attachment plate protrudes horizontally outwardly from thehead plate and supports the piece of docking equipment outwardly of theheadplate.

In a sixth separate aspect, the present invention is a probe stationcapable of mating to a tester that has a larger footprint than the probestation. The probe station includes a headplate and at least one dockingequipment supporting plate that extends outwardly from the headplate andsupports at least one piece of docking equipment at a location distancedfrom the headplate.

In a seventh aspect, the present invention is a method of retrofitting aprobe station having a head plate, so that the probe station is adaptedto mate with a predetermined probe card dish and any tester out of a setof testers. Fastening and alignment items are provided and installed onthe head plate. Further, a set of tooling plates is provided, eachhaving fastening and alignment items adapted to mate to the fasteningand alignment items on the head plate and defining an aperture designedto engage the predetermined probe card dish. The user may then select adesired one of the tooling plates and mate and fasten the selectedtooling plate to the head plate using the alignment and fastening items.

The foregoing and other objectives, features and advantages of theinvention will be more readily understood upon consideration of thefollowing detailed description of the preferred embodiment(s), taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a probe station-tester mating pair wherein theprobe station has been retrofitted according to the method of thepresent invention.

FIG. 2 is a top view of the probe station of FIG. 1.

FIG. 3 is an exploded perspective view of a portion of the probe stationof FIG. 1, showing some of the details of the retrofitting of thepresent invention.

FIG. 4 is a perspective view of a tooling plate and docking equipmentattached to the tooling plate.

FIG. 5 is a perspective view of another embodiment of a tooling plate.

BEST MODES FOR CARRYING OUT THE INVENTION

To perform one preferred method of retrofitting a probe stationaccording to the present invention, 0.3 mm (12 mils) of material ismachined away from the top of the head plate 12 of the probe station 10(both items have been introduced in the Background section) to form ahead plate-tooling plate attachment region 34 (FIG. 3). A pair ofthrough-holes (not shown) is drilled through the attachment region 34 ofthe head plate 12 to permit the attachment of a pair of dowel pins 38.

In addition a sequence of threaded holes 44 are machined just inside theperiphery of attachment region 34. The method of retrofitting a probestation that is the subject of the present invention is accomplishedwith the use of a tooling plate 110 as shown in FIGS. 1 and 2.Spring-loaded screws are set into a set of apertures 113, to permit therapid attachment of plate 110 to a retrofitted probe station. The bottomside of plate 110 defines dowel pin locator holes 120, which areconfigured to mate with dowel pins 38 and thereby facilitate the precisepositioning of plate 110. In one preferred embodiment the dowel pins 38are sited with great precision relative to the center of aperture 14 toensure correct alignment and positioning of a tooling plate 110.

The tooling plate 110, defines a tooling plate major aperture 112 forsupporting a probe card dish. A rim 122, adapted for probe card dishattachment is defined about aperture 112. A set of bosses 124, each sunkwith a threaded hole 126, ease the attachment of the probe card dish.Referring to FIG. 4, in some instances a set of docking equipment 130 isincluded as a part of an alternative tooling plate 110′ so that theinstallation of plate 110′ renders the probe station 10 ready to dockwith a tester of choice 18.

Ideally, a number of tooling plates 110′ could be provided, each onefitted with a distinct set of docking equipment 130 adapted to dock witha particular tester. In this manner, a semiconductor manufacturingfacility that owns a number of testers and a number of probe stationscould dock any one of a number of testers with any one of a number ofprobe stations. Moreover, if more than one probe station was retrofittedto accept any one out of a number of tooling plates 110′, than any oneof these testers could be placed in service with any probe station forwhich a matable plate 110′ was available.

It should be expressly noted that by producing a set of tooling plates,each of which has a standardized set of location and attachment items,and by modifying a set of probe stations so that each one has astandardized set of location and attachment items designed to mate tothe tooling plate location and attachment items, that a greatflexibility can be achieved in the sense that any of the probe stationscan be mated to any of the tooling plates and thereby to any tester forwhich such a tooling plate is available. This technique appears to beunknown in the prior art and can be applied even to probe stations ofdiffering makes, such as the popular brands TSK®, TEL® and EG®.

In an alternative preferred embodiment, no depression is machined inhead plate 12. Dowell pins 38 and threaded holes 44 are provided on thetop surface of head plate 12 and a tooling plate 110 is attached on topof head plate 12.

In one preferred embodiment a second set of threaded holes 44′ isprovided in head plate attachment region 34 for the attachment of asmaller tooling plate 110. Such a smaller tooling plate 110 wouldtypically be made to fit a probe station 10 having a smaller head plate.By providing the second set of threaded holes 44′ a probe station 10 ismade available for retrofitting with tooling plates 110 made primarilyfor a different line of probe stations 10 having smaller head plates 12.

Referring again to FIGS. 1-2, in some instances, a probe station willhave a head plate that is fairly small and will, further, have anobstacle 19 such as the cover for the device that loads the wafers ontothe probe card dish (the “loader cover”). It may not be possible to dockthis type of probe station to a tester without moving the probe carddish location away from the obstacle. To do this, the original headplate aperture 14 is enlarged by region 208 (FIG. 3), and a toolingplate 210 (FIG. 5) is provided having a major aperture 212 (FIG. 5) thatis not centered with respect to the remainder of the tooling plate 210.When tooling plate 210 is installed the major aperture 212 is locateddifferently from the original head plate major aperture 14 and isfurther away from the obstacle, thereby permitting a tester of choice todock to tooling plate 210 without encountering the obstacle.

In this embodiment the docking equipment 220 is included on a set ofdocking equipment plates 222. To facilitate the correct attachment ofplates 222 to head plate 12, head plate 12 is machined in similar mannerto the machining of attachment region 34 but nearer to its edge to formdocking equipment plate attachment regions (not shown) which wouldinclude location and attachment items such as threaded holes and dowelpins.

It should be noted that to successfully implement the embodiment shownin FIGS. 1 and 2, that the software that drives the tester and probestation must be adjusted to account for the difference in locationbetween the tooling plate major aperture 212 and head plate originalmajor aperture 14.

The terms and expressions which have been employed in the foregoingspecification are used as terms of description and not of limitation,and there is no intention, in the use of such terms and expressions, ofexcluding, equivalents of the features shown and described or portionsthereof, it being recognized that the scope of the invention is definedand limited only by the claims which follow.

1. An apparatus for installation on the head plate of a probe stationused in testing semiconductor devices, the apparatus comprising: a probecard dish and a probe card supported by the probe card dish; a removabletooling plate configured to be connectable to and completelydisconnectable from the head plate of the probe station, the toolingplate having first and second opposed major surfaces, the tooling platebeing formed with a major aperture in which the probe card dish isreceived; and docking equipment mounted to one of the first and secondmajor surfaces, the docking equipment configured to facilitate dockingof a tester to the probe station.
 2. The apparatus of claim 1, whereinthe tooling plate comprises a rim portion circumscribing the majoraperture for supporting a probe card dish positioned in the majoraperture.
 3. The apparatus of claim 1, wherein the tooling platecomprises at least one fastening item for releasably mounting thetooling plate to the head plate of the probe station.
 4. The apparatusof claim 1, wherein the tooling plate comprises at least one alignmenthole dimensioned to receive a respective alignment pin on the head plateto facilitate alignment of the tooling plate on the head plate.
 5. Anapparatus for installation on the head plate of a probe station used intesting semiconductor devices, the apparatus comprising: a removabletooling plate configured to be connectable to and completelydisconnectable from the head plate of the probe station, the toolingplate having first and second opposed major surfaces; and dockingequipment mounted to one of the first and second major surfaces, thedocking equipment configured to facilitate docking of a tester to theprobe station; wherein the tooling plate comprises a major aperture anda rim portion circumscribing the major aperture for supporting a probecard dish positioned in the major aperture; wherein the rim portioncomprises a plurality of circumferentially spaced bosses, each formedwith a hole for receiving a fastener for coupling the probe card dish tothe rim portion.
 6. An apparatus for installation on the head plate of aprobe station used in testing semiconductor devices, the apparatuscomprising: a removable tooling plate configured to be connectable toand completely disconnectable from the head plate of the probe station,the tooling plate having first and second opposed major surfaces; anddocking equipment mounted to one of the first and second major surfaces,the docking equipment configured to facilitate docking of a tester tothe probe station; wherein the tooling plate comprises at least onefastening item for releasably mounting the tooling plate to the headplate of the probe station; wherein the at least one fastening itemcomprises at least one spring-loaded screw for tightening into arespective hole in the head plate.
 7. A system for testing semiconductordevices, comprising: a probe card dish and a probe card supported by theprobe card dish; a probe station having a head plate; a tester fordocking with the probe station during testing of a semiconductor device;a tooling plate for supporting the probe card dish, the tooling plateadapted to couple to the head plate of the probe station and havingfirst and second opposed major surfaces; and docking equipment mountedto one of the first and second major surfaces of the tooling plate, thedocking equipment configured to facilitate docking of the tester to theprobe station.
 8. The system of claim 7, wherein the tester has dockingequipment configured to mate with the docking equipment on the toolingplate.
 9. The system of claim 7, wherein the head plate has a head plateaperture and a recessed area surrounding the head plate aperture forreceiving the tooling plate.
 10. The system of claim 7, wherein thetooling plate has at least one fastening item for releasably mountingthe tooling plate to the head plate.
 11. The system of claim 7, whereinthe head plate has a head plate aperture and the tooling plate is formedwith a major aperture dimensioned to receive the probe card dish, themajor aperture of the tooling plate at least partially overlapping thehead plate aperture so as to position the probe card dish for testing asemiconductor device in the probe station.
 12. The system of claim 7,wherein the docking equipment comprises at least one piece of dockingequipment adapted to mate with a piece of docking equipment on thetester.
 13. The system of claim 7, wherein the head plate has at leastone alignment pin and the tooling plate has at least one alignment holefor receiving the alignment pin to facilitate alignment of the toolingplate on the head plate.
 14. A system for testing semiconductor devices,comprising: a probe station having a head plate; a tester for dockingwith the probe station during testing of a semiconductor device; atooling plate for supporting a probe card dish, the tooling plateadapted to couple to the head plate of the probe station and havingfirst and second opposed major surfaces; and docking equipment mountedto one of the first and second major surfaces of the tooling plate, thedocking equipment configured to facilitate docking of the tester to theprobe station; wherein the head plate has a head plate aperture and thetooling plate is formed with a major aperture dimensioned to receive theprobe card dish, the major aperture of the tooling plate at leastpartially overlapping the head plate aperture so as to position theprobe card dish for testing a semiconductor device in the probe station;wherein the major aperture of the tooling plate is off center from thehead plate aperture.
 15. A system for testing semiconductor devices,comprising: a probe station having a head plate; a tester for dockingwith the probe station during testing of a semiconductor device; atooling plate for supporting a probe card dish, the tooling plateadapted to couple to the head plate of the probe station and havingfirst and second opposed major surfaces; and docking equipment mountedto one of the first and second major surfaces of the tooling plate, thedocking equipment configured to facilitate docking of the tester to theprobe station; wherein the tooling plate comprises a major aperture forreceiving a probe card dish, a rim portion circumscribing the aperture,and a plurality of circumferentially spaced bosses, each formed with ahole for receiving a fastener for coupling the probe card dish to therim portion.
 16. A method for using a probe station used in testingsemiconductor devices, the method comprising: positioning a first probecard dish in an aperture defined in a first tooling plate; mountingfirst docking equipment to an upper surface of the tooling plate; andmounting the tooling plate to an upper surface of a head plate of theprobe station.
 17. The method of claim 16, further comprising:positioning a first semiconductor device in the probe station; docking afirst tester to the docking equipment on the tooling plate; and testingthe semiconductor device.
 18. The method of claim 17, furthercomprising: removing the first tooling plate from the head plate;positioning a second probe card dish in an aperture defined in a secondtooling plate; mounting second docking equipment to an upper surface ofthe second tooling plate, the second docking equipment being differentthan the first docking equipment; mounting the second tooling plate tothe upper surface of the head plate; docking a second tester to thesecond docking equipment; positioning a second semiconductor device inthe probe station; and testing the second semiconductor device.
 19. Themethod of claim 17, wherein docking a first tester to the dockingequipment on the tooling plate comprises mating at least one piece ofdocking equipment on the tooling plate with a corresponding piece ofdocking equipment on the tester.
 20. The method of claim 16, furthercomprising positioning the first tooling plate in a recess formed in thehead plate of the probe station.
 21. The method of claim 16, whereinmounting the tooling plate to an upper surface of the head plate of theprobe station comprises aligning an alignment item on the tooling platewith a corresponding alignment item on the head plate of the probestation.
 22. The method of claim 16, comprising mounting the toolingplate to an upper surface of the head plate of the probe station suchthat the aperture of the tooling plate at least partially overlaps anaperture in the head plate.
 23. A method for using a probe station usedin testing semiconductor devices, the method comprising: mounting afirst tooling plate to the head plate of a probe station; positioning aprobe card dish supporting a probe card in a first aperture in thetooling plate; mounting first docking equipment to the tooling plate;and docking a first tester to the docking equipment.
 24. The method ofclaim 23, wherein the first aperture is off center from an aperture inthe head plate.
 25. The method of claim 23, wherein mounting a firsttooling plate to the head plate of a probe station comprises mountingthe first tooling plate in a recess in the head plate.
 26. The method ofclaim 23, further comprising aligning the first tooling plate withalignment items on the head plate.
 27. A method for using a probestation used in testing semiconductor devices, the method comprising:mounting a first tooling plate to the head plate of a probe station;mounting first docking equipment to the tooling plate; docking a firsttester to the docking equipment; removing the first tooling plate fromthe head plate; mounting a second tooling plate to the head plate;mounting second docking equipment to the second tooling plate, thesecond docking equipment being adapted to dock a second tester that isdifferent than the first tester; and docking the second tester to thedocking equipment.